The aseptic barriers in surgical medical field are well known. They take the form of rubber gloves, gowns, masks, drapes, as well as wrappers for materials which have been subjected to sterilization. An aseptic barrier has been defined as a material placed between an aseptic area, such as an operative incision, and areas which harbor microorganisms with the purpose of preventing the spread of bacteria into the sterile zone. Such a definition was included in an article "Aseptic Barriers" which the present inventor authored with Warner W. Carlson, which was published in Archives of Surgery, August 1963, Vol 87 pp 288-296, a publication of the American Medical Association. "How Bacteria Get from Here to There: The Basics of Surgical Asepsis", was also written by the present inventor and was published in Infections in Surgery, April 1985, pp 239 and 267. As identified in these articles moisture in the material will allow bacteria to be transmitted through the material. Stated more broadly, bacteria are transported from one area to another by some vehicle such as dust, water, or a human or other animate vector. When we consider bacterial "strike through" in relation to aseptic barriers, the transmission by a vehicle, rather than motility per se, is the factor of major importance. It is, therefore, imperative that a barrier material be impervious to bacterial vehicles such as water, if it is to be effective.
Another article co-authored by the present inventor relating to the need for aseptic barriers and that the aseptic barrier be impervious to the passage of water, is an editorial that appeared in the February 1952 edition of the American Journal of Surgery, Vol LXXXIII, No.2 pages 125-126.
The only mode of transfer of viruses, bacteria or other pathogens is by being carried by air or gaseous medium either by droplets of air or strike through. The transfer of pathogens from person to person is known to frequently occur from hand to hand contact. This is particularly true in the case of the common cold.
The common cold is often, if not usually, caused by one of the rhinoviruses, of which there were, a decade ago, at least 89 distinct serologic types with at least one subtype recognized. Thus it is improbable that any vaccine will become available.
Furthermore, there are at present no known antivirals to these rhinoviruses, and very little effort is being expended upon such a discovery; nor is there much hope of finding one. It appears that our only defense against the common cold is the prevention of its spread.
This implies an intimate knowledge of the mechanisms of its spread. This would be followed by a logistically and economically feasible method of its interruption. I believe that the latter is both mechanically even profitably possible.
Gwaltney and Hendley have shown that the rhinovirus is spread principally if not only through the nasal mucus membrane, in a series of articles: 1) Hendley J. O., Mika L. A., Gwaltney J. M. Jr: Evaluation of Virucidal Compounds for Inactivation of Rhinovirus on Hands, Antimicrob. Agents Chemother. Vol 14. NO. 5:690-694, 2) Gwaltney, J. M., Jr. and J. O. Hendley. 1977 Rhinovirus transmission: One if by Air, Two if by Hand. Trans. Am. Clin. Climatol Assoc. 89: 194-200, 3) Gwaltney, J. M., Jr. P. B. Moskalski, and J. O. Hendley. 1978. Hand to Hand Transmission of Rhinovirus Colds. Ann. Intern. Med. 88:463-467. The common cold is a nose-to-nose (or nose to eye) disease. It is from nose to hand, by handshake to another hand to another nose transmission.
The obvious potential source, the transmission of the virus by droplets or droplet nuclei either does not or very rarely takes place. The droplets of sneeze contain little if any nasal secretion. This was beautifully demonstrated by Duguid of the Department of Bacteriology in (Edinburgh, J. P. Duguid. 1945. The Numbers and the Sites of Origin of the Droplets Expelled During Expiratory Activities. Edinburgh Medical Journal 52:385-401). In 1897 and in 1899 Flugge demonstrated that small droplets are often emitted from the mouth during a variety of expiratory activity. Normal breathing, sneezing, coughing, speaking and laughing produce microbe-laden droplets. A variety of methods have been employed to demonstrate and even count the droplets, so that it has been shown that a sneeze may produce from a few hundred thousand to a few million droplets. Droplets larger and 100 microns rapidly drop to the floor. Smaller droplets evaporate before reaching the floor, and through evaporation form residues of "droplet nuclei" which may contain viable microorganisms, an, like smoke, may remain airborne for hours or even days.
But Duguid proved that nearly all of the droplets in sneezing or talking have the salivary pool in the front of the mouth as their source. There is little if any contribution from nasal secretions. A single cough may produce droplets from the throat, but mostly from the front of the mouth (again the salivary pool), ranging in number from a few hundred to many thousand with content from the front of the mouth and the fauces.
Gwaltney and Hendley quote the work of several authors who have shown the nose and even the eye were splendid portals of entry for respiratory viruses with minute doses producing the infection. They concluded that contamination of the hands of the infected individual, hand-to-hand contact with a new host by contaminated fingers would spread the infection.
Furthermore, they showed that nose blowing resulted in the contamination of the hands. They recovered virus from half of the hands of persons with natural or experimentally induced colds with a single sampling, and in 90 percent with repeated sampling. On the other hand, virus was found in the saliva of only half of infected persons, and then only in low titer. No large volume titers were produced by sneezing and coughing by infected volunteers with experimental colds. Also close contact between coughers and sneezers did not cross infect normals. Yet a ten second hand-to-hand contact resulted in demonstrable transfer in 20 to 28 exposures. Furthermore, virus on the recipient hand led to infection in eight of nine instances when the contaminated finger was deliberately placed in contact with the mucosa in the nose.
Facial tissue, such as "KLEENEX.TM.", poses no barrier to the contamination of the hands no matter how many layers are used. This has been demonstrated in surgical barriers, and has also shown how microorganisms progress from one site to another.
Hendley, Mika, and Gwaltney have suggested the use of a virucide, such as alcohol, on the hands. The problem with using virucide is that it would be bulky to carry around at all times when a person might need to blow his/her nose. If a dispenser of virucide was not around it is quite possible and in fact probable that most individuals would forego using it. The pathogens should be prevented from coming into contact with the hand of the infected individual in the first place. Thus there is little or no protection for the person who comes into contact with a facial tissue that has been used by an infected individual to blow his nose.
Stated simply, the use of handkerchiefs and paper tissues which transfer the noxious agent from the discharges from a person's nose to his hands continues without exception and via the receptors hand to his nose.
While the relationship between an aseptic barrier and the fact that such barrier must be impervious to the passage of water or any kind of aqueous solution is known in the art, heretofore, it has been unrecognized that these principles have application to the transfer of viruses and bacteria from person to person.